(Adds details from House panel statement, background) June 25 (Reuters) - U.S. lawmakers on Friday announced an investigation into the approval and pricing of Biogen Inc’s Alzheimer’s drug, Aduhelm, amid concerns over its steep price and doubts if the clinical evidence proves the drug works. The drug, which has a list price of $56,000 per year, was approved by the U.S. regulators as the first treatment to attack a likely cause of Alzheimer’s on June 7. “We have serious concerns about the steep price of Biogen’s new Alzheimer’s drug Aduhelm and the process that led to its approval despite questions about the drug’s clinical benefit,” House Committee on Oversight and Reform said in a statement. The investigation has been announced by Rep. Carolyn Maloney, chairwoman of the Committee on Oversight and Reform, and Rep. Frank Pallone, Jr., Chairman of the Committee on Energy and Commerce. At $56,000 a year, the Kaiser Family Foundation estimates that Medicare could spend $57 billion or more per year on Aduhelm, which is more than Medicare Part B spends on all other drugs combined, the House Committee said. The FDA approved the drug - despite strong objection from its own expert advisory panel - for all patients with Alzheimer’s, although Aduhelm has only been tested for patients in the early stages of the disease. Shares of the drugmaker were down nearly 1% in after-market trading. Reporting by Dania Nadeem in Bengaluru; Editing by Arun Koyyur Our Standards: The Thomson Reuters Trust Principles.